Unprofessional and unreliable business

We have been struggling to get the project finished for the last 9months now. The project was started in September 2021, and have been struggling since November 2021 to get the last part completed. We have even received a letter where it was stated that we would be reimbursed but that letter means nothing as the owner believes in making only empty promises. His work has a supposed 4year guarantee on and when you ask him to come and fix things all you get is empty promises from him. He owes us R7500 or the completion of the project but it all is empty promises. Constant reasons why the project cannot be worked on. I have now seen on both Facebook and hello peter that this has happened to others. This is not a reliable business to use.